I know that fire in a few words is the exothermic reaction of a fuel with an oxidizing agent, but I can't fully understand what exactly happens to piece of wood when it is ignited. How do molecules start producing a flame? In other words, what is the chemistry behind the production of flame?
4
$\begingroup$
$\endgroup$
-
1$\begingroup$ Fire is about physics rather than chemistry. Sure, there is a chemical dimension to it, but it is quite trivial: $\ce{C + O2->CO2}$ (that is, if we burn coal; wood is somewhat more complicated, but whatever). $\endgroup$ – Ivan Neretin May 23 '16 at 18:26
-
$\begingroup$ related chemistry.stackexchange.com/questions/1254/… does not describe start of fire unfortunately $\endgroup$ – Mithoron May 23 '16 at 19:07
-
$\begingroup$ chemistry.stackexchange.com/questions/44526/… is useful here $\endgroup$ – Mithoron May 23 '16 at 19:08
-
$\begingroup$ and chemistry.stackexchange.com/questions/6954/… $\endgroup$ – Mithoron May 23 '16 at 19:11
-
$\begingroup$ This is a classic: youtube.com/watch?v=ITpDrdtGAmo (Always copy Feynman's answer) $\endgroup$ – colnegn Jun 12 '16 at 23:03
4
$\begingroup$
$\endgroup$
https://www.youtube.com/watch?v=B0E4PX3e3RE It feels somewhat weird to answer my own question but I think this video describes exactly what I wanted. As it supports, when heat is applied to a piece of wood, some bonds of the molecules that make up wood, break and thus different compounds are formed. These compounds are not held back by some force and so they are released in the air. When these compounds meet atmospheric oxygen, under heat (=energy), they burn and thus more heat is released along with carbon dioxide and water. That stage can be described as ignition. Finally, this produced heat is able to preserve the fire.
answered May 23 '16 at 19:35
-
1$\begingroup$ Answering your own question is good. There is nothing wrong with it on Stack Exchange. $\endgroup$ – bon May 23 '16 at 21:32
-
3$\begingroup$ The only bit you are missing is that, for a fire to start, the reaction has to be self-sustaining when the applied heat/flame is removed. In other words the energy released from the initial reaction has to be large enough that the reaction continues to happen when the initial heat source is removed. $\endgroup$ – matt_black May 24 '16 at 15:10
